A.O. Smith BTX-100/GDHE-50 – Upper Probe Open

The control system has detected over 56,000 ohms from the Temperature Probe on top of the water heater.

Check Temperature Probe plug and socket connection at CCB’s J7 Socket (page 36). Perform close visual inspection of the pins inside the plug and socket – ensure plugs and sockets are mating properly and providing good contact.

Check all wiring between the Temperature Probe and the J7 Socket on the CCB. Repair/replace anything worn or damaged.

Unplug J7 plug from CCB, check resistance between the two black wires in the plug end with an ohm meter. If resistance is above 56,000 ohms – replace the Temperature Probe.

Call the technical support phone number shown on the water heater labeling for further assistance if the problem has not been corrected after performing the procedures outlined here.